How to position selected element at the middle of a Row

MainActivity.kt

package com.slaviboy.test

import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.compose.foundation.clickable
import androidx.compose.foundation.horizontalScroll
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Row
import androidx.compose.foundation.layout.padding
import androidx.compose.foundation.layout.width
import androidx.compose.foundation.layout.wrapContentHeight
import androidx.compose.foundation.rememberScrollState
import androidx.compose.material3.Text
import androidx.compose.runtime.Composable
import androidx.compose.runtime.LaunchedEffect
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableStateListOf
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.runtime.rememberCoroutineScope
import androidx.compose.runtime.setValue
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.layout.onGloballyPositioned
import androidx.compose.ui.layout.positionInParent
import androidx.compose.ui.platform.LocalDensity
import androidx.compose.ui.unit.dp
import androidx.compose.ui.unit.sp
import kotlinx.coroutines.launch
import kotlin.math.roundToInt

class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            Test()
        }
    }
}

data class Balance(
    val amount: String,
    val isSelected: Boolean
)

@Composable
fun Test() {
    val scope = rememberCoroutineScope()
    val scrollState = rememberScrollState()
    val list = remember {
        mutableStateListOf(
            Balance("$342.23", false),
            Balance("€23,342.23", false),
            Balance("£9,934.30", false),
            Balance("BGN 543.43", false),
            Balance("BLR 43.35", true),
            Balance("HUN 492.35", false),
            Balance("JPY 5326", false)
        )
    }
    var selectionFlag by remember {
        mutableStateOf(true)
    }
    var scrollToPosition by remember {
        mutableStateOf(0f)
    }
    LaunchedEffect(selectionFlag) {
        scope.launch {
            scrollState.animateScrollTo(scrollToPosition.roundToInt())
        }
    }
    val paddingHorizontal = 50.dp
    val paddingHorizontalPx = with(LocalDensity.current) { paddingHorizontal.toPx() }
    val parentWidth = 400.dp
    val parentWidthPx = with(LocalDensity.current) { parentWidth.toPx() }
    Row(
        horizontalArrangement = Arrangement.Center,
        verticalAlignment = Alignment.Bottom,
        modifier = Modifier
            .padding(horizontal = paddingHorizontal)
            .width(parentWidth)
            .wrapContentHeight()
            .horizontalScroll(scrollState)
    ) {
        list.forEachIndexed { i, item ->
            val (amount, isSelected) = item
            Text(
                text = amount,
                color = if (isSelected) {
                    Color.Red
                } else {
                    Color.Red.copy(
                        alpha = 0.2f
                    )
                },
                fontSize = 15.sp,
                modifier = Modifier
                    .padding(
                        horizontal = 10.dp
                    )
                    .onGloballyPositioned { coordinates ->
                        if (isSelected) {
                            val x = coordinates.positionInParent().x
                            val width = coordinates.size.width
                            scrollToPosition = x - (parentWidthPx / 2f) + paddingHorizontalPx + (width / 2f)
                        }
                    }
                    .clickable {
                        val selectedIndex = list.indexOfFirst { it.isSelected }
                        list[i] = list[i].copy(isSelected = true)
                        list[selectedIndex] = list[selectedIndex].copy(isSelected = false)
                        selectionFlag = !selectionFlag
                    }
            )
        }
    }
}